You’ve probably noticed the variety of body shapes of runners in a start corral (except for the elites). To calm my hilariously overblown pre-race nerves, I usually size up the group around me, which in the 9-10min./mile area, runs the gamut of height and width. “Uh-oh,” I think, “That girl has some long get-away sticks! What is she doing here? She’s going to breeze right past me.” Nevertheless, once everyone takes off, I am repeatedly shocked to find that most of my predictions are false. Long Legs McGee might finish twenty minutes after me, but a hulking man with tree trunks for limbs might already be nom-nom-ing post-race refreshments by the time I cross the finish line.
So, what gives? This week, I tried to discover if there’s an ideal body type for runners.
In the 1940’s, constitutional psychologist Herbert Sheldon identified three body types, or somatotypes, which can supposedly be defined by their unique physiological characteristics. While constitutional psychology sought to associate body types with human temperaments, these three somatotypes are often used to describe athletic builds as well.
(Source)
Ectomorphs are small-boned and slim, with long limbs and muscles. They don’t store fat very well.
Mesomorphs have medium-sized bones, with a solid chest and torso and low levels of fat. It’s the typical “upside-down triangle” shape: a small waist and broad shoulders.
Endomorphs have large bones and a wide waist. Because they are predisposed to fat storage, they have difficulty losing weight.
(Probably the least flattering photo of me of all time.)
Which body type does science say is best suited for long-distance running?
If you guessed the ectomorph, you were partially right! According to this article from The Globe and Mail, a small ectomorph is the best size and shape for marathoning. However, being an ectomorph isn’t enough; excellent biomechanics also play a crucial role.
You can also check out this infographic from the same article shows how different body types fare in marathons, with typical injuries they sustain during training:
If you’re unconvinced by the superiority of the small ectomorph, read this article that The New York Times ran a few years ago about body types and sports. It supports the idea that in distance running, smaller and lighter wins the race…literally.
However, all this is not to discourage mesomorphs and endomorphs from lacing up their shoes and running marathons. Having a “non-ideal” body type for this sport doesn’t mean that your legs are going to fall off spontaneously as soon as you hit high mileage. Nor does being a perfect ectomorph mean that you are destined for Olympic Greatness.
As my mom often reminds me, you don’t have to be good at everything you do. Running is no exception. Even if my Henry VIII-esque calves would better suit me for something like ice-skating or hula dancing, I like running, and that’s reason enough to stick with it.
So the next time an ectomorph passes you, don’t worry! If you’re an endomorph, just remember that your predisposition for fat storage means that you’ll live way longer in a period of extreme famine anyway. Who’s laughing now, ectos?!?




